Lathe



1. s LAPP.

' LATHE.

APPLICATION FILED SEPT. 15, 1919.

El AQKQ 1' 8 Patented Aug. 29, 1922.

human stares rarest clerics.-

JOHITS. LAPIP, 0F LE ROY, NEW YORK, ASSIGNOR T0 LAP? INSULATOR COMPANY,OF

LE BOY, NEW YORK, A CORPORATION OF NEW YORK.

I LATHE.

earners.

Specification of Letters Patent. Pat ent-(ed Aug. 29, 1922..

Application filed September 15, 1919. Serial No. 323,809.

To all whom it may concern:

Be it known that T, JOHN S. LAPP, a citizen of the United States, and aresident of Le Roy, in the county of Genesee and State of New York, havemade a new and. useful Invention in- Lathes, of which the following is aspecification.

My invention relates to lathes and in parpeated trials. An example ofsuch a condi-- tion is presented by'the practiseof turning articles fromclay mixtures after partial drying but before firing.

The process of firing will cause the article, as turned in the lathe, toshrink appreciably but the amount or proportion of such shrinkage varieswith different clay mixtures and with the dryness of the molded articleat the time itis turned.

The problem is to produce quantities of articles which shall be similarin outline and size, not only at the time they are turned but afterthey'have been fired and consequently have shrunk. Toprovide and apply aseparate templet for each variation in the material .or its conditionwhen turned wouldinvolve a considerable expense and waste. of time. .Bymeans of my invention the necessity of a plurality of templets isavoided.

I use a single templet to guide thecutting tool to produce an articlesimilar in sha e but varying in size from the templet. y providing meansfor adjusting the templet and varying its action on the cutting toolaccordingly, a'variation in the sizes of the turned articles may be madecommensurate with the degree of subsequent shrinkage which has beendetermined by experiment or otherwise.

The means by which it accomplish my object is illustrated in theaccompanying drawings in which Figure 1 is a view of a lathe being usedto produce insulators and Fig. 2 is a preferred detail of one of theparts.

The insulator 1 is of any suitable clay composition which is machineableafter dryingbut before firing. It is ordinarily turned when in a leatherhard state. lit is mounted on the spindle 2 of the lathe and is rotatedin the usual manner by a driving belt 3. At the back of the lathe andextending upwardly is an upright 4t, fixed with respect to-the lathe andprovided at its top, some distance above the lathe, with a bracket 5.This bracket'extends over the lathe and at its outer extremity supportsa tool holder 8 by an universal joint 7;

The lower end of tool holder 6 is provided with a square hole for theaccommodation of the shank of a cutting tool 8. A I

set screw '9 secures the tool 8 when in posit1on.-

shortdistance above tool 8 is a guiding finger 10 having a shank secured.to tool holder 6, approximately parallel with the shank of tool 8, andprovided with an upright finger 11. through finger 11 at any pointshould have the same outline as a horizontal section through a conicalfigure whose base has the contour of the cutting edge of tool 8 andwhose apex is the center of the universal joint 7.

Cooperating with finger 11 is a guiding templet 12 which may be securedby any suitable means to upright 4. T have shown the templet held byclamping members 13 whiclrare fastened to upright 4 by means of angularclips 14. The slots 15 in clips 14, through which the fastening bolts 16pass, are elongated to permit vertical adjustment of the templet. I

Operation: in starting production of an article, the templet is locatedby judgment and clamped in position; tool holder 6 is swung to bringguiding finger 11 in contact with templet 12'and, as it is moved alongsame, cutting tool 8 will give insulator 1 an outline similar to thetemplet outline but differing therefrom in size in the same ratio as thedistance D-1 bears to distance D -2. By varying the vertical location oftemplet '11, the ratio between the sizes of the templet and the latheproduct will be varied ac-. cordingly.

While it is possible to calculate the per-- centage of shrinkage and setthe templet accordingly, in practise, I find it more suitable to testthe insulators as they come from the kiln and if they are runningoversize A horizontal. section I the finished product only, and withoutre-' gard to the size of the article as it is produced by the lathe.Another advanta e is the ease with which the size of the athe product isvaried without any change of templets. By using guiding templets,workmen may produce the lathe product much more re idly than if thefeeding of the cutting too is done by judgment only and the templetusedfor gaging only.

If the contour of the cutting-edge of tool 8 is an erect a circle, as ismost common, I prefer to ut1l1ze a roller 17, mounted on as indle 18,for the guiding finger contact.

ig. -2 shows such an arrangement and I have indicated the rollershouldered at 19 and supported by a collar 20. By lowering the collaruntil the larger circumference of roller 17 bears against templet 12,cutting tool 8 will turn a larger article than will be produced by thecontact of the smaller circumference of the roller with the templet. Inthis Way the guiding toolmay be adapted to feed the cutting tool for aroughing cut andlthen by' shiftingthe roller-collar and without anyadjustment of the templet, a finishing cut may be taken. While thisfeature may only be incorporated when the cutting edge is circular, sucha limitation is not serious as it is in comparatively few articles inwhich the cutting edge is required to be non-circular in outline. 7

As the tool holder is swun from a point, the variation between tern Tetand turned article is produced longitu inally as well as transversely.The height of bracket 5 should be suchthat the arc described by thetools in a vertical terially fores orten the longitudinal movement ofthe tools. y

In the illustration of my device I have shown an arrangement of thetemplet and tools which will result in a lathe product placed below thespindle center line instead of above the advantages-and functions of thepresent arrangement are retained but lane willbe insufi'icient to Ina--smal er scale. Such an arrangement would 1 be especially desirable wherethe lathe product was subject to expansion "in subse uent steps. Icontemplate such variation 0 my device in the construction of lathes-inacoordance'with my disclosure It is not essential that the contour ofthe templet be to the same scale as the finished article although thatscale seems preferable and is likely to be theone adopted in mostcases.But the-operation of the lathe is independent of the scale, relationbetween the templet and the finished article.

I claim V v 1. The combination with a rotatable work spindle, of a toolholder supported'at one end by a universal joint, a cutting tool carriedby said holder, a templet and means carried by said holder between saidjoint and said tool for co-operating with said templet in controllingthe movement'of said tool.

2. The combination with a rotatable work spindle, of a support suspendedfor universal movement, a cutting tool carried by said support, atemplet located above said cuttin tool and a templet follower carried bysai support above said tool.

3. The'combination with a rotatable work spindle, of a swinging rod suported by a universal joint at a substantial distance from said spindle,a cutting tool mounted on said rod adjacent said' spi'ndle, a ide spacedfrom said spindle and a guide Edger carried by said rod for cooperationwith said guide. j

4. The combination with'a rotatable work spindle, of a universallymounted tool support rod, a cutting tool carried by said rod adjacentsaid spindle, a vertically adjustable templet above said spindle and atemplet follower carried by said rod above said tool. I

5. The combination with a rotatable work spindle, of a sup ort adistance above said spindle, a tool ho der' pivoted from said sup portand capable of swinging toward and from said spindle and longitudinall'thereof, a cutting tool carried by said too holder, a templet above saidspindle and a templet follower carried by said tool holder: above ber,1919.

, JOHN S. LAPP.

